Fuel injection pump



D. J. DESCHAMPS FUEL INJECTION PUMP 8 Sheets-Sheet 1 Filed sept. 15, 1945 d/.I ATTORNEYS Oct.' 28, 1947. Y D. J. DESCHAMPS 2,429,806

FUEL IJEc'rIoN PUMP 8 Sheets-Sheet 2V D. J. DESCHAMPS FUEL INJECTIONPUIP Oct.' 2s, 1947.

Fi1ed sept. 15, 1945 .B sheets-sheet s D. J. DE'sHAMPs FUEL INJECTIONPUMP 8 Sheets-Sheet 4 Fle'd Sept. 15, 1945 I NvENToR @my l ampws, nrw zwel ATTORNEYS Oct. 2s, 1947.

Oct 28., 1947 D. JQDEscHAMAPs' 2,429,805

FUEL INJECTION PUMP v Filed sept. 15, 1945 s sheets-sheet 5 @Aw/Lrg 8Sheets-Sheet 6 W f f 14111 f D. J. DESCHAMPS FUEL INJECTION PUMP Filedsept. 15, 1945 oct. 28,'1947.

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ATTORNEYS Oct 28, 1947. D. J. DESCHAMPS FUEL .INJECTION PUMP SSheeths-Sheet 7 File@ Sept. 15, 1945 Oct 28 1947. D. J. DESCHAMPS FUELVINJECTION PUMP I 8 Sheets-Sheet 8 -lN'vENToR Filed Sept. l5, 1945 7m,Dam, mami'. ruuudg ArroRNEYs Patented von. 2s, 1947 FUEL iNJaorlQN vDesire J. Deschamps, Rutherford, N. J., assigner to Deschamps FuelInjection Corporation, New York, N. Y., a corporation of New YorkApplication September 15, 1945 Serial No. 616,532

17 claims. 1

This invention relates to fuel injection pumps and has for its objectthe provision of an improved high speed pump for injecting liquid fuelinto the cylinders of internal combustion engines.

Pumps of this kind frequently comprise a plurality of pump cylindersusually, referred to as bushings or cylinder bushings, in which operateplungers actuated by suitable reciprocating mechanism to cause theapplication of pressure to the liquid fuel and its discharge throughtubing to the respective engine cylinders. In one form of pump of thistype widely used, the length nf the period of injection and thereforethe quantity of fuel injected by each stroke of the plunger in itscylinder is varied to suit the power demands of the engine by turningthe plunger axially on its cylinder.

Mechanism under the control of the engine governor or throttle lever isprovided for simultaneously turning the vseveral plungers of the pump toeiect control of the output'l of the pump as a whole, that is, of allthe pump cylinders taken together. Difliculties, however, have beenexperienced in transmitting the rotary motion to the plunger while it isreciprocating, and one of the commonest arrangements in use heretoforehas been to provide a cross arm on the plunger to assist in impartingthe turning movement thereto. These cross arms, however, must be madeintegral with the plunger and consequently the cost of the pump plungershas been high. One of the objects of the present invention is toovercome these difculties, eliminating such T-shaped plungers andproviding a construction which is fully as reliable in operation andless expensive to manufacture.

Another object of the inventionvis to simplify the mechanism for turningthe respective vplungers in unison.

Another object of the invention is to provide an improved mechanism foradjusting the output of the individual cylinders while the pump isoperating in order to facilitate the calibration of the pump.

A further object of the invention is to provide (Cl. S-173) drawings andthe f'ouowmg detailed description for the adjustment of the output ofthe individual cylinders from the outside of the pump housing.

A still further object of the invention is tov of one embodiment of theinvention which is given by way of example. In these drawings:

Fig. 1 is a central longitudinal sectional viewl of the improved fuelinjection pump taken taken on line I-I o! Fig. 3;

Fig. 2is a view in elevation looking from the left-hand of Fig. 1;

Fig. 3 is a similar view looking` from the righthand of Fig. 1;

Fig. 4 is a central longitudinal section of a single pumping unit of thepump, drawn to an enlarged scale; y

Fig. 5 is a View of certain parts shown in Fig. 4 looking at the bottomofthat figure, some of these parts being shown broken away and some insection;

Fig. 6 is a. transverse section taken online 6--6 of Fig. `4;

Fig. 'I is a sectional view taken on line 1--1' of Fig. 2;V

Fig. 8 is a transverse section taken on line 8-8 of Fig. 1;

Fig. 9 is a partial end view of the pump looking frmlthe left of Fig. 1with parts broken away and shown in fragmentary section on line 9-9 ofFig. 1;

Fig. 10 is a. fragmentary section similar to that of Fig.- 9 showing amodified construction, the section being taken on line Ill-I0 of Fig.11;

Fig. 11 is'an outside view looking downward on the parts shown in Fig.10;

Fig. 12 is a sectional view similar to Fig. 10 but i taken on lineI2--l2 of Fig. 11;

Fig. 13 is a sectional view taken on line i3-l3 of Fig. 11;

Figs. 14 to 16 inclusive are views of a single cylinder aim plunger witha part of the cylinder brokenaway'and shown in section to show theporting of the plunger, the plunger being shown at three differentpoints of its stroke;

Figs. 17 to 19 inclusive are similar views with the plunger 'at thesame-point of its stroke but turned on its axis corresponding to dierentoutputs;

Figs. 20 to 25 inclusive are similar v'iews of a modification andcorrespond respectively with Figs. 14 to 19 inclusive; and

Figs. 26 to 31 inclusive are also similar views of a furthermodification corresponding to Figs. 14 to 19 inclusive.

Referring now to the accompanying drawings, the pump comprises a mainhousing I which is a cylindrical shell extendingfsomewhat less thanone-half the length of the pump and provided at its inner end with aflange 2 and at its outer end with a flange 3. A mounting flange orplate 4 is adjacent flange 2 by which the pump is secured on themounting pad of the internal combustion engine. Housing I carries asuitable number of pump cylinders or bushings 5, the pump illustratedhaving y nine cylinders. Each cylinder is provided with a reciprocatingplunger 6 which, through a tappet mechanism indicated generally bynumeral 1, is operatively associated with the pump actuating elementwhich is shown as a floatingwobble plate 8, butwhich may also consist ofa plain wobble plate or a face cam. The respective plungers are operatedin a well under-l stood manner on their working or fuel-injectingstrokes by means of the actuating element 8 and on their return strokesby means of coil springs 9 appropriately. associated with the tappetmecha nism 1.

The several cylinders 5 are supported in apertures in internal flanges Iand II at the opposite ends of main housing member I. the cylindersagainst longitudinal movement they are themselves flanged at their outerends as indicated at I2, these flanges I2 being received within counterbores in the apertures for the cylinders in internal flanges IIL Thetappet members 'I are ycarried in a tappet housing I3 provided withapertures, for guiding the tappet member 1, which are in longitudinalalignment with the apertures in the internal flanges III and Il of mainhousing member I which support the pump cylinders. Tapp'et housing I3 isprovidedy with an integral cylindrical extension I4 extending toward theinner or righthand end of the pump and terminating in a flange I5 bywhich the tappet housing is supported on main housing member I. Thetappet mechanism and wobble plate 8 are enclosed by a cup-shaped covermember I6 having a .flange I1 which ts over flange I5, both this coverand tappet housing I3 being secured to main housing member I by a seriesof screws I8 which are tapped into flange 3.

Main housing I and mounting flange 4 are secured together not only bymeans of a series of screws I9 which are tapped into ange 2, but also bymeans of a hollow tubular supporting member 26 which extendssubstantially from end to end of the pump. Member 28 is provided with ashoulder 2l which engages the inner surface of internal flange I0 ofhousing I and projects through a central opening in this flange and alsoin mounting flange 4 and terminates in a threaded portion 22. 0n thisthreaded portion 22 there is a nut 23, the inner end of which is turnedup tight against the outer surface of mounting flange 4. Hollowsupporting member is received in a central opening in internal flange IIofvhousing I and also in a similar opening in tappet housing I3 and,being firmly secured to mounting flange 4 and the inner end of housingI, serves to rigidify the entire pump structure.

Hollow supporting member 26 also serves lto support the bearings of theshaft 24 of actuating element 8. This is a tubular shaft extending fromend to end of the pump and rotating in ball bearings 25 and 26. Adjacentbearing 25 there is a ball bearing 21 constructed to take the endwisethrust on the shaft resulting ,from the'plunger reaction on wobble plate8. Bearings 25 and A21 are disposed adjacent each other, and their innerbearing races are held in position 1by means of a nut 28 threaded on anenlargement on shaft 24.

.-bore of hollow supporting member 20 and is held therein by means of asnap ring 28, fitting into a groove in this bore. The outer bearing raceof bearing 25 is held in position by 'a spacing sleeve 29, theright-hand end of whichl is incontact with a lubricant distributorhousing 30. Another snap ring 3| at the right-hand end of housing 30holds both the housing and spacing sleeve 29 in position within hollowsupporting member 20. Inner ball bearing 26 is positioned against aninternal rib 32 formed on the interior of supporting member 20 and by asnap ring 33.

Actuating element 8 is of the so-called floating or non-rotating type,being mounted on a pair of ball bearings 34 constructed to resistendwise thrust. The outer race's of these bearings are held in positionwithin the hollow hub of actuating element 8 by means of a snap ring 35.

To restrain The inner races are mounted on an extension 36 on hollowshaft 24, the axis ofthisrextension being disposed at a suitable angleto that of shaft 24. These bearing races are held in position on thisshaft extension by means of a nut 31.

Tubular shaft 24 constitutesv merely a supporting shaft for actuatingelement 8, and the pump is driven by means of a quill or flexible shaft38. This shaft is splined at 38 for connection to the pump driving shaftprovided'on the engine, and its opposite end has a squared enlargement40 which is received within a similarly formed opening adjacent theouter end of hollow shaft 24.

The gasoline or other fuel to be pumped is admitted to the pump throughan inlet opening 4I, this liquid being usually supplied by means of atransfer pump which introduces it into inlet 4I at a pressure of aboutl5 lbs. per square inch. A second opening (not shown) similar andadjacent to inlet 4I is preferably provided for connection to a vaporremoving device. The fuel entering inlet 4I is received within anannular inlet chamber 42 within main housing I and outside of hollowsupporting member 20. From inlet chamber 42 the fuel is admitted to theworking space 43 of each ofthe nine pump cylinders or bushings 5 throughinlet ports 44 which are controlled in a manner to be described.

The fuel. is ejected from working space 43 through an outlet opening 45drilled through mounting flange 4. Each of these outlet openings isclosed by a thimble-shaped automatic or spring-actuated valve member 46.As the fuel is ejected from the working space 43 it forces valve member46 open and escapes through an injection passage 41 which is drilled inmounting flange 4 to communicate with one of the openingsl 48 throughwhich passes one of the holding screws (not shown) which fasten the pumpto the engine mounting pad. 11; wiube understood that these screws areof a hollow construction` and that each communicates with a duct withinthe engine leading to the fuel injection valvey of one of the enginecylinders. Y

As indicated in the introduction, the amount of fuel injected into theengine cylinders by the operation of pump plungers 6, or in other wordsthe volumetric outputs of the pumping spaces 43, is adjusted orregulated by axially turning plungers 6. The turning of these plungerscontrols the closing and opening of ports 44 in a well understoodmanner.

Although there is shown in Figs, 1 and 4 only a single port 44 for eachcylinder 5, each cylinder bushing is in fact provided with two of theseports positioned diametriclly opposite each other (see Figs.v 14-19).The closing andv opening of these two ports is controlled lby means oitytwo diametrically opposite lugs 49 on 'each yof thev plungers 5. Theselugs have the same congura,

tion and, as shown in Fig. 1. their upper edges 50 are nat, i. e., atright angles to the axis of surfaces 51 of fingers 55 on key drivinggear 53 in all positions of the reciprocating plunger.

By means of this constructions. change in the `angular position of gear53 will turn the plunger a similar-amount whether the plunger isstationary or reciprocating, thereby regulating or acl-- justing thehelical port-controlling edges 5| and A hencethe amount the plunger,while their lower edges 5I each have the form of a'helix. -As shown inFigs. 1 and 4 plunger 5 is at the end of its inward or back stroke andthe upperedges 55 of lugs y4 9 have uncovered the two ports 44, and fuelis free to ilow into the' working space 43 through'these ports frominlet chamber 42'.

As plunger 5 moves to the right on a forward or working stroke the outeredges 55 close ports 44 at the instant they pass the right-hand edges ofthese ports. I'he injectionof fuel into the engine cylinder willtherefore start at this point. In-

.iection continues until the 'inner helical edges 5I The mechanism forturning plungers 6 whilethey are reciprocating is illustrated in Figs. 1and 4 to 8 inclusive, Oxie of the principal parts of this mechanism is asmall gear 53 arranged for free rotation on each of the cylinders 5which, for this purpose, has an end portion 52 of reduced diameterprojecting to the left of internal flange Il. The thrust of spring 9 isreceived by gear 53, the right-hand end of this spring bearing against acollar 54 thereon. Consequently, to enable gear 53 to turn easily, evenwhen spring 9 is under full compression,.a ball thrust bearing 55 isplaced on the right-hand side of gear 53 between it and the surface ofinternal ilarige Il of housing I. Each of the gears 53 has a pair ofelongated fingers 55, the inner faces 51 of which are fixed in spacedparallel relation, as shown in Fig. 5.

At the left-hand end of each of plungers 6 there is a. flanged springretaining sleeve 58, having a longitudinally projecting key portion 59,the sides of which ilt with a sliding t between the parallel spaced`surfaces 51. inner part of key portion 59 rests within a key The offuel injected into -the engine cylinders.

Referringnow to Figs. 'l and 8, the several key driving gears 53, onefor eachof the nine pump cylinders 5, are interconnected with oneanother by means of a large idler gear 54 which is mounted for rotationon the exterior of hollow supporting member (see Figs. 8 and 1). Gear 54rotates on member 20 between theside of internal flange Il and a snapring 55 fitted into an annular' groove inthe surface oi this member.

Instead of turning the several gearsv 53 by means of -a vturning ordriving mechanism connected with gear 54, this gear is employed merelyas an idler gear and the output control lever is arranged to actuate oneof the gears 53, the motion imparted to this one gear being transmitted`to all of the others by the idler gear 64.

" Thus the control lever, indicated at 66, is xed slot cut in thesurface of plunger 6. Spring- Y surface of the'plunger.

The sloping outer surfaces of the two-piece ring 6I engage an inner4conical surface 62 provided at the left-hand portion of sleeve 58.These parts are held in locked position by the pressure of spring 9, theleft-hand end of which engages a flange ,53 on sleeve 58.l Sleeve 58being thus xed at the end of plunger 6, key 59 4is Yheld immovably inkey slot 50 and reciprocates with the plunger, the key,` however, vbeingof suicient length so that it is engaged by the on the end of a shaftA51 which is arranged to rotate on an outward extension 58 at one sideof main housing I, as shown in Figs. 2, 3 and 6. On the inner end ofshaft 51 there is a. gear 59 which engages the teeth of the nearest gear53. The number of teeth in gear 59 may be so chosen as to provide anydesired angular movement of output control member 55 in adjusting thepump from zero to maximum output.

It will be understood that it is important to have the outputs of therespective pumping cylinders varied uniformly in order to maintainequality of load between the various engine cylinders. This requiresexact adjustment of the ,helical control 'edges 5| of the several pumpplungers. Such precise adjustment is ordinarily diflicult to obtain in agear driven mechanism, but in the mechanism as above described itisattained because of the fact thatthe pressure of the liquid in theworking spaces 43 of the pump cylinders, when it is released throughuncovering of the spill ports 44 by the helical control edges 5I, actsupon these helically inclined edges in such a way as to tendto turn allof the plungers in the same direction. The same sides of the respectivegear teeth are therefore always maintained in contact and backlashbetween them is prevented.

Consequently there is never a reversal of the pressure between any ofthese gear teeth, either between those of any of the gears 53 and idlergear 54 or between the teeth of gear 59 and those of the gear 53 withwhich it meshes; In other words, the movement of output control lever 55transmits force through the gear train to move .gears -53 in only -onedirection of movement of the control lever. In its .opposite directionof movement the force transmission is also .in the opposite direction,that is, the uid pressure on the helical edges 5l tends to cause gears53 to rotate and this rotation is restrained by the output control lever55 and the teeth of the gear train.

7 The utilization of gear 54 as an idler gear and the application ofactuating gear 59 directly to one of the plunger rotating gears 53 hasthe advantage of placing the actuating mechanism on the outside of thepump and frees the central actuating mechanism.` I

The tappet mechanism' 1 is of thimble-like construction as shown in Fig.4, the skirtl 10 of the thimble being cylindrical so as to slide in 1the guiding apertures in tappet housing I3 and guide the slippers 1I,maintaining them in alignment with their respectiveplungers 6.as theyare actuated in their reciprocating movement by the wobble plate 8.Skirt 10 has a predetermined length in order to operate as an eiectiveguide means and spring 9 is telescoped within skirt 10 for a substantialportion, of its length. The inner end of plunger 6 bears directlyagainst lthe end of tappet 1, thev compression of spring operating atall times to urge the tappet and slipper 1I` against the surface of thewobble plate 8. Tappet 1 floats between the end of the plunger and thewobble plate, there being no connection attaching the tappet to theplunger.

In the pump of the present invention the pump cylinders or bushings 5are not mounted Iier-l manently in housing I by means of a press fit,"as is customary, but these parts are assembled with a sliding ilt. Thismakes it possible to remove individual cylinders for servicing and inaddition facilitates manufacture of the pump. It is possible to finishgrind and lap or hone the bore of the cylinder bushings as separate andinterchangeable units instead of requiring that such finishingoperations be done after the bushings have been pressed in place in thehousing.

There is an objection to assembling the bushings in the housing with apress fit, as it sets up stress in the walls of the bushings which lateron sometimes causes distortion of the bore and sticking of the plunger.Also, when the bushings are inserted with a press iit the metal remains'under stress of compression so that temperature changes, stress put onthe parts when the pump is in operation, and other factors may causedeformation of the bore of such bushings.

By mounting the pump cylinders 5 with a sliding iit in housing I,provision is made for another feature of the present invention, namely,the calibration or adjustment of the several cylinders of the pump toproduce equal outputs from all cylinders. This is of importance because,although the cylinder bushings and other parts of the pump which mayaffect the output are machined within small tolerances, the accumulationof these tolerances when taken for the several parts which concur invthe motion of the plungers and in the location of the .ports may begreat enough to cause important discrepancies in the timing of theporting and thus of the outputs of the several pumping units of thepump.

Consequently, it is necessary to provide some means for adjusting theindividual pumping units to obtain uniformity of output in thecalibration of the pump. As shown in detail in Fig. 9, provision is madefor rotating each of the pump cylinders 5 independently of the others,so that the cylinder ports 4,4 can be angularly adjusted with respect tothe `helical edges 5I of the port control lugs 49 on the plungers. Toaccomplish this cylinders 5 are provided opposite the internal flange, II of housing I with a series of worm gear teeth 12 preferably formed bymilling cuts equally spaced around the circumference of the cylinder,and an adjusting screw 13 having threads 14 engaging these teeth isprovided.

These screws, for each of the cylinders 5, are positionedinapertresdrilled'in ange I which openinto a circular recess 15 extending aroundthe pump housing. Adjusting screws 13 each have an enlarged portion 16having inner and outer shoulders at either side and beyond which isvasquared end adapted to receive an adjusting wrench. Enlargement 18 isreceived within, a

`counter bore at the outer end of the adjusting screw aperture.

The adjusting screw is held fixed to prevent vlongitudinal movement asit is turned in either direction to eiect the turning and adjustment ofthe pump cylinder 5. For this purpose the inner shoulder of enlargement16 cooperates with a shoulder formed at the bottom of the eountersunkportion of the screw aperture and the outer shoulder of enlargement 16is positioned against a snap ring 11 which is received within annulargroove in the counter bore.

VTo obtain a close fit between these two shoulders which will allowrotation of screws 13 substantially without endwise movement, shimwashers 18 are placed at the innershoulder of enlargement 16. In orderto facilitate the assembly of screws 13 in their apertures a supply ofthese' washers in varying thicknessesl is provided so that an exact fitof the inner and .outer shoulders of enlargement 16 can be obtained.

It will be understood that in calibrating the pump each of the cylinders5 of the pumps nine pumping units is adjusted by applying a wrench toits adjusting screw 13 until the cylinder produces a predeterminedvolumetric output. Then adjusting screw 13 is locked in position bymeans of a locking/,screw 18, the inner end of which is forced againstthe surface of' enlargement 16 as shown in Fig. 9. Locking screws 19 areprotected against unintentional release by means of screws which closethe apertures in which screws 19 are threaded.

The outer ends of the apertures in which adjusting screws 13 are locatedare closed by screw Both these screw plugs 8| and screws 60 areaccessible for removal within the annular recess 15 in the pump housing,and this recess maybe closed to protect these parts and to improve theappearance of the pump by means of a nexible band 82 encircling the pumpand clamped in position by means of a connecting screw 83.

In the modification shown in Figs. 1 to 13 inclusive, the constructionof the parts for adjusting the cylinders 5 is identical with that justdescribed except the arrangement for locking the parts in adjustedposition after calibration. Instead of providing the locking screw 19for engaging the enlargement of adjusting screw 13, the cylinderbushings 5 are locked directly by means of a friction shoe 84 (Figs. 12and 13). One of these shoes 84 is provided between each two bushings 5in a suitable opening provided in internal flange IIa. v j

Shoes 84 have arcuate surfaces at their oppositev ends so arranged thatwhen the shoe is forced outwardly these surfaces will be wedges intofrictional engagement with the cylindrical surfaces of the two bushings5. Each shoe 84 is provided with an adjusting screw 85 which isaccessible within annular recess 15a in the pump housing at a pointadjacent alternate screw plugs 8| which cover adjusting screws 13. Withthis construction, after each two cylinder bushings 5 have been adjustedby turning their respective adjusting screws 13 to bring their output tothe desired standard, their u common locking screw 85 is turned up,forcing the shoe '84 at its inner end into engagement with thesecylinders.

The leakage of liquid from pumping space 43 back to the inlet chamber 42is prevented by the engagement of the inner face of flange I2 ofcylinder bushing with the shoulder formed at the bottom 'of thecountersunk portion of the cylinder aperture in internal ange I0 of thepump housing. A lapped fit is preferably provided at this point. It will'b e understood that the pres sure between these two surfaces increaseswith the increase of the pressure in pumping space 43 as the plungeradvances. In order to maintain the surfaces in contact with one anotheratall times a spring washer 86, shown in enlarged View in Fig. 4, isprovided. To prevent leakage of fuel from inlet chamber 42 between thesurface of cylinder bushing 5 and the aperture of internal flange I I, acomposition softrubber packing ring 81 is provided in suitable grooves88 (Fig. 4) formed in the surface of each cylinder bushing.

The pump is lubricated by oil underpressure supplied from the pressurelubricating system of n in each of the piungers also serves to lubricatethe inter-fitting surfaces of key member 59 and key driving fingers 56.Lubricant escapes from radial passages |03 between the outer surface ofcylinder bushings 5 and their apertures, both to 1ubricate thesesurfaces and the ball thrust bearings 55 and gears 53 and 64.

The lubricant collects in the portion of the pump to the left ofinternal flange I I, and returns to the interior of the engine. For thispurpose a horizontal passageway |0911 (Fig. 3) is.

drilled through a rib |09b formed on the outside cylindrical surface ofmain housing I. Passageway |09a extends from the left-hand face ofinternal ange II to the right-hand face of external flange 2.- Theright-hand end of this passageway communicates with a series of drilledpassages shown in dotted lines in Fig. 3, which convey the lubricant tothe lowermost of a' series of circular openings in extension ||1 (Fig,l), through which the lubricant flows into the interior of the enginehousing. A Vent passageway |09 is drilled through lubricant distributor95.

An alternate means of supplying lubricating -oil to the lubricatingsystem just described is'provided in case the engine on which the pumpis to be used'has an oil supply opening in the vmounting pad. Mountingflange or plate 4 is ing |20 passes through flange 4 and communiwhichmakes a running yfitwith the central part Distributor 95 has a radialpassage 91'between groove 94 and an outer annular space 98 betweendistributor 95 and housing 30. Opening through the cylindrical part ofhousing 3 0 there are a number of radial openings 99 through which theoil may flow to an annular groove |00 on the interior wall of hollowsupporting member 20. A

number of radial passages |0I conduct the lubricant from groove |00 to alarge annular groove |02 formed in the aperture through internal flangeI I which receives hollow supporting member 20.

From this large annular groove |02 there are spaced openings |03, oneleading to each of the apertures in which cylinder bushings 5 arepositioned. The lubricant then passes through suitable grooves and aninclined passageway |04 to an annular groove |05 in the surface ofplunger 6 from which it lubricates the surface of the plunger and isalso conducted through a radial opening |06 to a longitudinal passage|01 in the plunger (Fig. 4) which delivers lubricant at its left-handend to the tappet mechanism 1.

Some of the lubricant escapes between the end of the plunger and thetappet whichabuts against it and flows through passages I08`in thecylindrical skirt 10 to lubricate the surface of this skirt in itsvguiding aperture in the tappet housing.

Lubricant also 'flows through apertures (not shown) in the tappetmechanism to the interior of slippers 1| and lubricates the surface ofthe wobble plate 8 and bearings 34 and 35. Lubricant escaping from theend of longitudinal aperture |01 'cates with a groove |2| machined inthe outer end surface of main pump housing A tube |22 conveys the oilfrom this groove to a drilled passage |23 in internal flange I and thispassage communicates with annular groove |02.

Referring again to Figs. 14 to 19 inclusive, these figures show theporting and controlling lug arrangement of the cylinders and plungersfor fixed timing of the beginning of the injection period. Figsi 14, l5and 16 show different positions of one ofthe plungers 6 during a singleworking stroke, the controlling lugs`49 being turned to the angularposition where the pump has zero effective stroke land consequentlynooutput.

In Fig. 14 the plunger is ready to commence a forward or working stroke.In Fig. 15 the plunger has advanced until the forward edges 50 ofcontrol lugs 49 have covered inlet ports 44. At the same instant thehelical lower edges of lugs 49 are commencing to uncover the lower edgesof ports 44 which serve as pressure relief or spill gates. At thisinstant the liquid fuel which 'fills compression space 43 above theplunger, begins to be forced outward through., kports 44 to return toinlet chamber 42. In Fig.

in Fig. 19 the plunger is shownturned to the position of maximumeffective stroke.

Figs. 20 to 25 inclusive correspond with Figs. 14 to 19 inclusive, toillustrates. pump cylinder 5 having therein a modified form of plunger6d whose port controlling lugs 49a are arranged to provide xed timing ofthe ending Iof the injec- 14 to 19 inclusive. Figs. 20, 21 and 22 showthe same plunger 6a in different positions of its stroke as previouslydescribed in connection with Figs. 14, 15 and 16. Figs. 423, 24 and 25show the plunger 6a at the instant of start of the injection period forthree different pump outputs as described in connection with Figs. 17,18 and 19.

Figs. 26 to 31 inclusive shows a second modiflcation of the portcontrolling lugs on the, plunger, in this instance to produce fixedtiming of the center of the injection period. For this purposecontrolling lugs 49h are provided with helical control edges at bothends. Thus helical edges 50D control the start of the injection periodand control edges Bib the ending of the injecthat is to say, for fixedtiming of the start of the injection, fixed timing of the ending of theinjection, and fixed timing of the center of the injection, it will beobservedfrom Figs. 14 to 31 inclusive that substantial amounts of fuelmust be returned to the inlet fuel chamber 42 while the plungercontinues Vto 'the end of its stroke after the end of the injection, theamounts being particularly large in the case of fixed timing of thebeginning and fixed timing at the center of the injection. l

It is important, particularly with the injection of volatile fuel suchas gasoline, that the injection periodbe terminated with great rapidity,that is to say, substantially without lapse of time. In order to bringthis about it is necessary to provide for the fuel to flow from theworking space 43 to and through the two ports 44 at a low velocity so asto reduce the pressure drop in the fuel passages. This brings aboutquick reduction in the pressure within working space 43 and consequentlyquick closing of the discharge valve 46. f

InA order to accomplish this the plunger construction of the presentinvention includes a large axial passageway H0 extending from ther endof the plungers 6, 6a and 6b to a point opposite the extreme ends of theport controlling lugs 49, 49a and 49h. At this point there is pro-`vided in the outer `surface of the plunger a circular groove III ofample depth and width. as shown in Figs. 4 and 14 to 31 inclusive.Groove Il merges into the somewhat triangular spaces Il! disposedinwardly of the helical control edges 5I as shown in Figs. 14 to 19inclusive. Connecting axial passageway I I0 with groove ill are twolarge cross passageways I I3.

By this arrangement of fuel passageways thev area of such passageways isample to provide for the ow of the fuel from working space 43 to thespill ports 44 at low velocity so as to bring about an extremely quickreduction of the pressure With' l2 in the working space at the instantthe spill ports are uncovered.

In addition to these passageways there are also preferably provided thediagonally opposite longitudinal grooves I I4, the primary purpose ofwhich, however, is to facilitate manufacture; specifically the millingof the port controlling lugs 49. 'Ihese grooves assist in conveying theliquid from the working space 43 to the triangular spaces H2 (Fig. 14)and thence to the ports 44.

Referring again to Fig. 1, 4and particularly to the outlet or dischargevalves 46, it has hereto- In the automatic valve construction of thepresent pump valve member 46 is of thimble shape having a cylindricalbody portion Iliand a reduced end portion terminating in asemi-spherical valve H6. Cylindrical skirt portion H5 nts in acylindrical guide opening which is machined in an annular projection iI1 on mounting flange or plate 4. A coil spring H8 tted within skirt Il1at one end and held at its opposite end by a removable plug I|9maintains the valve in engagement with its seat. This construction hasthe advantages of a ball check valve without the difilculty of guiding aloose ball.

Valve member 46 with its cylindrical skirt and semi-spherical valve endconcentric with the skirt, can be produced without difficulty -byordinary production methods. Furthermore, the machining of the valveseat at the right-hand end of opening is eliminated. It is onlynecessary to drill opening 45 concentric with the aperture in whichcylindrical skirt H5 is guided. It is not necessary to machine a seatfor the valve but the edges of this hole 45 are left sharp, the seatbeing formed by the hammering of the valve itself. In

thi-s way a very narrow seat is formed which is preferable to a widevalve seat and the hammering of its edges produces a hard surfacebecause of the cold working of the metal.

The pump of the present construction has numerous advantages, some ofwhich have been mentioneddescribing it. It will be understood that thevarious features of the pump may be modified as to the precisearrangement and embodiment as described herein, and that changes of thisnature can be madeA without departing from the scope of the inventionwhich is set forth in the appended claims.

I claim:

1. In a pump having a relatively reciprocable plunger and cylinder andwhose plunger is rotatable to vary the pump output, mechanism forturning said plunger while it is reciprocating comprising a key member,a longitudinal key slot therefor in the surface of the plunger, meansfor positioning said key in the slot, a key driving member having aslidable connection with said key, means for mounting the same forrotation concentric with the plunger, and means for turning said keydriving member.

2f In a pump having a relatively reciprocable 13 plunger and cylinderand whose vplunger is rotatable 'to vary the pump output, mechanism forturning said plunger while it is reciprocating comprising a singlelongitudinal key slot in the.

" for -rotation concentric with the plunger, and

means for turning said driving member.

3. In a pump having a relatively reciprocable i plunger and cylinder andwhose plunger is rotatable to vary the pump output, a coil springsurrounding said plunger to move the same on one Y of its strokes, asleeve-like pump output control member mounted for rotation on .thecylinder adjacent its inner end, means interconnecting said sleeve-likemember and said plunger opera'ble to transmit rotational movementtherebetween while the plunger is reciprocating, means interconnectingthe outer ends of said spring and plunger, and the inner end of saidspring engaging one side of said output control member,

whereby said control member, spring and plunger turn as a unit to adjustthe output of the pump.

4. In a pump having a relatively reciprocal plunger and cylinder-andwhose plunger is rotatable to vary-the pump output, a coil spring-surrounding said plunger t0 move the same on one of its strokes, aspring retainer fixed to said plunger adjacent its outer end, alongitudinal key slot inthe surface of said plunger, a key memberprojecting from said spring retainer and positioned thereby in saidslot, a sleeve-like pumpv output control member mounted for rotation yonsaid cylinder adjacent its. inner end, a pair of fingersprojecting fromsaid member parallel with the plunger, said fingers having parallelfaces engaging the opposite sides of said key to transmit the rotationof said control member to said plunger' while the plunger isreciprocating, a shoulder on said control member adjacent said fingers,said coil spring having its ends engaging respectively said shoulder andsaid spring retainer, whereby said control member, spring and plungerturn as a unit to adjust the output of the pump.

5. In a multi-cylinder pump having relatively reciprocable plungers andcylinders and whose y plungers are rotatable in their respectivecylinders to vary the output thereof, means for turning said plungerssimultaneously to vary the pump output, a housing supporting saidcylinders to allow rotation of each cylinder individually to adjust theoutput thereof, each of said cylinders having vworm gear teeth thereon,an outwardly directed aperture in said housing adjacent each cylinder,an adjusting screw disposed in said aperture having its threads engagingsaid teeth, means to position said screw against longitudinal movementin said aperture during rotation of the screw, and means for clampingthe screw in adjusted position.l

6; In a multi-cylinderpump having relatively vreciprocable plungers andcylinders and whose plungers are rotatable in their respective cylindersto vary the output thereof, means for turning said plungerssimultaneously to vary the pump output, a housing supporting saidcylinders to allow rotation of each cylinder individually to adjust thevoutput thereof, each of said cylinders 14 cylinder, and anadjusting'screw disposed in. said aperture having its threads engagingsaid'teeth,

a pair of oppositely directed shoulders on said screw and cooperatingshoulder means within 'said aperture to position said screw againstlongitudinal movement during rotation vof the screw, and means forclamping said screw in adjusted 7. In a multi-cylinder pump havingrelatively reciprocable plungers and cylinders and whose plungers arerotatable intheir respective cylinders to vary the output thereof, meansfor turning said plungers simultaneously to vary the pump output, ahousing supporting said cylinders to allow rotation of each cylinderindividually to adjust the output thereof, each of said cylindersshaving worm gear teeth thereon, an outlwardly directed aperture in saidhousing adja-` y cent each cylinder, an adjusting screw disposed in saidaperture having its threads engaging said teeth, a circular recess inthe exterior of said housing, the outer ends of said adjusting screwsbeing disposed within said recess, and a removable ilexible bandcovering said recess.

' 8. In a multi-cylinder pump having relatively reciprocable plungersand cylinders and yvhose plungers are rotatable in their respective'cylinders to vary the output thereof, means for turning said plungerssimultaneously to vary the pump output, a housing supporting saidcylinders for individual rotation of each cylinder, mechanism associated-with said housing for turning each of said cylinders independently ofthe others to adjust the cylinder output, and' mechanism carried by saidhousing and coacting with the outside walls of said cylindersto lock thesame in adjusted position.

9. In a multi-cylinder pump'having relatively I reciprocable plungersand cylinders and whose plungers are rotatable in their respectivecylinders to vary the output thereof, means for turning said plungerssimultaneously to vary the pump output, a housing supporting said'cylinders for individual rotation of each cylinder, mechanism forturning each of said cylinders independentlyl of the others to adjustthe cylinder output, friction shoes engageablewith the surfaces of saidrespective cylin'ders, and means for moving said shoes into and out ofsuch engagement. y

10. In a multi-cylinder pump having relatively reciprocable plungers andcylinders Aand Whose plungers are rotatable in their respectivecylinders to vary the output thereof, means for turningv said plungerssimultaneously to vary the pump output, 'a housing supporting saidcylinders for individual rotation of each cylinder, mechanism forturning each of said cylinders independently of the others to adjust thecylinder output,

,a friction shoe positioned in said housing between each pair ofcylinders, and means for moving said shoe into and out of engagementwith both of having worm gear teeth thereon, anvoutwardly A saidcylinders simultaneously.

11. In a multi-cylinder pump having relatively reciprocable plungers andcylinders and whose plungers are rotatable in their respective cylindersto vary the output thereof, means for turningssaid plungerssimultaneously to vary the pump output,

a housing supporting said cylinders for individual rotation of eachcylinder, a circular recess in the exterior of said housing, mechanismwithin said recess for rotating. each of said cylinders independently ofthe others to adjust the cylinder output, and mechanism forlfrictionally locking.

said cylinders in adjusted position, said mechathe same disl put, andmechanism for frictionally locking said cylinders in adjusted position,both of said mechanisms having means for operating the same accessiblefrom the exterior of said housing.

13. In a multi-cylinder pump, a plurality of cylinders arrangedinparallel relation in a. circular row, plungers in said cylinders andmeans for reciprocating the same, said plungers being rotatable in therespective cylinders to vary the output thereof, the output beingcontrolled by a spill port in each cylinder uncovered by a lug on theplunger having an edge disposed at an angle to the axis of the plunger,an output vcontrol gear arranged to rotate on the inner en'd of each of.said cylinders, means interconnecting said re- 16 actuating memberoperatively associated with the tappet mechanisms of said pumping units,a main housing member having a circular row of apertures therein tosupport said cylinders, a central longitudinal opening in said housing,a

mounting ilange for the pump adjacent one end of said housing and havinga corresponding'opening therein, an elongated hollow supporting member.positioned in said central opening, means on said hollow supportingmember to secure said housing and said mounting iiange together, a shaftfor said actuating member, and bearings for said shaft disposed withinsaid hollow supporting member.

17. In a multi-cylinder pump having a plurality so.. said housing, meanson said hollow supporting member to secure said housing and saidmounting flange together, anda tappet housing remov- 14. In a pumphaving a relatively reciprocating a fuel inlet port in the side thereof,a plunger therein adapted to control said por-t, means' forreciprocating said plunger, an outlet passage from the cylinder, a valveseat in said passage, a pressure-operated valve cooperating with sal'dseat comprising a thimble-shaped member having a cylindrical skirt andterminating in a semi-spherical valve portion, a spring acting on saidvalve to bias said semi-cylindrical portion against said seat, andguiding means cooperating with said cylindrical skirt.

` 16. In a multi-cylinder pump having a plurality of pumping unitsarranged in parallel relation in a circular row, each comprising acylinder,A a plunger therein and tappet mechanism, a rotary ably securedtothe outer end of said main housing and having a central opening toreceive and engage said hollow supporting member.

DESIRE J. DESCHAMPS.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date l 1,697,853 Coursen Jan. 8, 19291,933,081 Stephan Oct. 31, 1933 2,160,735 HoiIer May 30, 1939 2,206,914Muller July 9, 1940 2,215,827 Ditto Sept. 24, 1940 $376,856 Hatch May29, 1945 2,388,462 Beeh Nov. 6, 1945 FOREIGN PATENTS- Number CountryDate 146,963 Great Britain Oct. 6, 1921 OTHER REFERENCES

